But on a KISS principle.
On the relay for the sebel ...
85 and 86 [I assume these are the coil connection of the relay] can be connected directly across the standard horn .. this will mean any inductive effects of the relay will be swamped by the standard horn!

87 [I assume this is one of the high current connectors of the relay] can be taken directly from the battery .. through a fuse for safety.

No CANBUSS connection is required with this wiring as the standard horn connection will take care of ignition key requirements etc.

[Suggest you test the assumed connections - connect terminals 85 and 86 directly to the battery, the other teminals unconnected to anything. The realy should click as the connection is made and unmade .. if not then something is wrong. ]

-------------------------------------------------
Driving a 20 Amp load (sebel horn) thought a capacitor .. would require an extreamly large capacitor!!!!! It is not going to happen.

Frank, thanks for the input. FYI and AP1 is an auxillary fuse panel. It is used to isolate the many gadgets from the bike's electrical system and prevent nasty melt downs.

Haven't meet Mrs. CANBus yet but I'm guessing the back EMF from the relay coil is screwing up the CANBus when the relay is de-activated (you let the horn switch go...)

Back EMF is the reverse current produced by the relay coil when you turn it off. You DO need a Diode to kill the back EMF, but the diode has to be reverse connected across the relay coil terminals, so it appears as a short circuit to any reverse voltage that appaears at the relay terminals.

Wire this correctly, and the problem should be gone. Get it wrong, and the diode goes west when you press the horn switch , and maybe the CANBus too!

EMF as you call it is not a product of horn button release. The Stebel cuts out while I still have the button depressed and the OEM horn continues to sound.

I have two stebel air horns on my '06 GT. Never a problem. I am going to buy a new GS so I hope all of you get this worked out. As all of you know...once you have a good horn you cannot live without it.

School solution on all CANBUS bikes is to leave the original horn connected to as it came from the factory and tap the relay into the horn circuit. The OEM horn is still there and the load change from the relay is negligible keeping the ZFE happy. You then drive the Stebel via the switched side of the relay from the battery and all is good. The relay alone will/should trip a ZFE fault on many if not all the CANBUS bikes.

What would the wiring diagram for that look like? Draw me a picture and I'm golden. Thanks!

-Rob

__________________
I can imagine a no more rewarding career. And any man who may be asked in this century what he did to make his life worthwhile, I think can respond with a good deal of pride and satisfaction: "I served in the United States Navy." JFK

"I rode a lot of dirt bikes when I was younger, so I trust the chain and sprockets more than that newfangled voodoo shaft stuff!" DolphinJohn

Sweet. Thanks! I gotta call 'stich and have 'em add an AP1 to my order.

-Rob

__________________
I can imagine a no more rewarding career. And any man who may be asked in this century what he did to make his life worthwhile, I think can respond with a good deal of pride and satisfaction: "I served in the United States Navy." JFK

"I rode a lot of dirt bikes when I was younger, so I trust the chain and sprockets more than that newfangled voodoo shaft stuff!" DolphinJohn

Thanks Diesel. That be it, just add the fuse. This will keep the CANBUS happy with it always seeing a functioning horn. The service manager at my dealer did this with his ST and I have also done it, never a problem.

__________________
I can imagine a no more rewarding career. And any man who may be asked in this century what he did to make his life worthwhile, I think can respond with a good deal of pride and satisfaction: "I served in the United States Navy." JFK

"I rode a lot of dirt bikes when I was younger, so I trust the chain and sprockets more than that newfangled voodoo shaft stuff!" DolphinJohn

Errr if that works then the OEM Horn is not directly connected to the canbuss but rather to a canbuss controller thingy ... as such the added relay does not connect to the canbuss but across the OEM Horn supply lines .. It is fundamentaly that you realise a relay will not directly function on a canbuss by itself!!!!

Dieselboy - if that connection works then you have a problem with your AP1 system ...

__________________
I can imagine a no more rewarding career. And any man who may be asked in this century what he did to make his life worthwhile, I think can respond with a good deal of pride and satisfaction: "I served in the United States Navy." JFK

"I rode a lot of dirt bikes when I was younger, so I trust the chain and sprockets more than that newfangled voodoo shaft stuff!" DolphinJohn

First, I have a 1200GS, the 800 is gonna have to wait awhile. That said, I believe the electronic systems are similar.

The ZFE senses high AND low current draw. The relay coil does not pull enough current and the ZFE shuts the circuit off because the current draw is "out of range". Add a 7.5 ohm, 25watt resistor (Mouser # 284-HS25-7.5F) across the relay coil and it will be fine. This is what I had to do for my 1200GS.

And FWIW, the canbus is just an industrial network that is used to send digital data. It does not do any "work" It's the telephone line, not the telephone.

First, I have a 1200GS, the 800 is gonna have to wait awhile. That said, I believe the electronic systems are similar.

The ZFE senses high AND low current draw. The relay coil does not pull enough current and the ZFE shuts the circuit off because the current draw is "out of range". Add a 7.5 ohm, 25watt resistor (Mouser # 284-HS25-7.5F) across the relay coil and it will be fine. This is what I had to do for my 1200GS.

And FWIW, the canbus is just an industrial network that is used to send digital data. It does not do any "work" It's the telephone line, not the telephone.

I assume you put the resistor in line between the relay and the CANBUS tap?

EDIT...after re-reading your post, of course, that is where it is. So you are saying the resistor draws enough current to keep the ZFE from noticing too low a current. Did you remove your OEM horn? If not I'm not sure I understand why you would need to draw more current.

As I stated earlier in this series, the CANBUS pushes (EDIT .2+) volts even with the ignition off, so I'm still looking to prevent that (in addition to figuring out this quandary).